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arXiv · 2212.10799

Bipartite quantum state discrimination and decomposable entanglement witness

Donghoon Ha·Jeong San Kim
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Abstract

We consider bipartite quantum state discrimination using positive-partial-transpose measurements and show that minimum-error discrimination by positive-partial-transpose measurements is closely related to entanglement witness. By using the concept of decomposable entanglement witness, we establish conditions on minimum-error discrimination by positive-partial-transpose measurements. We also provide conditions on the upper bound of the maximum success probability over all possible positive-partial-transpose measurements. Finally, we illustrate our results using examples of multidimensional bipartite quantum states.

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Donghoon Ha, Jeong San Kim. 2022-12-21. Bipartite quantum state discrimination and decomposable entanglement witness. https://doi.org/10.1103/physreva.107.052410

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